Present and future engines need to meet upcoming emissions legislation. Governmental regulations and environmental concerns have driven the need to reduce emissions from internal combustion engines. In The United States of America the Clean Air Act will require 90% to 95% reduction of the current level of emissions from internal combustion engines by the year 2007. Similar regulations are expected in Europe and other parts of the industrialized world.
The reduction of NOx production conventionally includes the use of catalytic converters, “clean” fuels, exhaust gas recirculation, and engine timing changes. These methods are generally expensive or too complicated to be readily commercially available.
Fuel improvements have occurred through emulsified fuels. When water is added to a fuel it forms an emulsion. An emulsified fuel lowers peak combustion temperature due to the water and thus reduces particulates and NOx formation. Internal combustion engines, in particular diesel engines, using emulsified fuels results in the combustion chamber producing lower NOx, hydrocarbons and particulate matter emissions.
Another complication facing modern compression ignited and spark ignited engines is the build up of particulate matter in the lubricating oil. The buildup of soot thickens the lubricating oil and can cause engine deposits. When the soot levels gets too high, the increase in oil viscosity results in poor lubrication at critical wear points of the engine. This poor lubrication results in high wear, the formulation of higher amounts of piston deposits, a loss in fuel economy occurs and increased exhaust emissions. The net result is a shorter effective life of the lubricating oil and exhaust emissions.
The problem remains that further reductions in pollutants especially NOx, particulate matters and hydrocarbons are required from engine emissions. The instant invention provides a solution to these problems.
It is needed that the engine, lubricating engine oil and fuel need to be integrated into a system to maximize the reduction of engine emission.
It has been found that engine emissions are reduced by using an emulsified fuel in combination with any engine oil, either a conventional engine oil or an ashless non-conventional engine oil.
It has been found that the engine oil that is consumed and burned in the engine reduces a portion of the total particulate matter and the emulsified fuel reduces the other component of the particulate matter. Furthermore, the synergy results in the further reduction of hydrocarbons and NOx emissions from an engine. Additionally, the use of an ashless engine oil further adds limited wear protection to the engine and reduces emissions.
The use of an emulsified fuel with a suitably selected (low ash or no ash and/or low phosphorus) engine oil synergistically reduces the emissions from an engine.